PHP SDK - Exchange Rates API

Installation

composer require exchangeratesapi/php

The official PHP SDK is coming soon! For now, use the native cURL/Guzzle examples below or create your own wrapper class.

Quick Start

Basic PHP Class

<?php

class ExchangeRatesAPI
{
    private $apiKey;
    private $baseURL = 'https://api.exchangeratesapi.com.au';

    public function __construct(string $apiKey)
    {
        $this->apiKey = $apiKey;
    }

    private function makeRequest(string $endpoint): array
    {
        $ch = curl_init();
        curl_setopt_array($ch, [
            CURLOPT_URL => $this->baseURL . $endpoint,
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_HTTPHEADER => [
                'Authorization: Bearer ' . $this->apiKey,
                'Content-Type: application/json',
                'User-Agent: PHP-ExchangeRatesAPI/1.0'
            ],
            CURLOPT_TIMEOUT => 30,
            CURLOPT_SSL_VERIFYPEER => true
        ]);

        $response = curl_exec($ch);
        $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        
        if (curl_error($ch)) {
            throw new Exception('cURL Error: ' . curl_error($ch));
        }
        
        curl_close($ch);

        $data = json_decode($response, true);
        
        if ($httpCode >= 400 || !$data['success']) {
            throw new Exception('API Error: ' . ($data['error']['info'] ?? 'Unknown error'));
        }

        return $data;
    }

    public function getLatestRates(): array
    {
        return $this->makeRequest('/latest');
    }

    public function getLatestRate(string $currency): array
    {
        return $this->makeRequest('/latest/' . $currency);
    }

    public function convert(string $from, string $to, float $amount, ?string $date = null): array
    {
        $params = http_build_query([
            'from' => $from,
            'to' => $to,
            'amount' => $amount,
            'date' => $date
        ]);

        return $this->makeRequest('/convert?' . $params);
    }

    public function getHistoricalRates(string $date): array
    {
        return $this->makeRequest('/' . $date);
    }

    public function getHistoricalRate(string $date, string $currency): array
    {
        return $this->makeRequest('/' . $date . '/' . $currency);
    }

    public function getTimeSeries(string $startDate, string $endDate, ?array $symbols = null): array
    {
        $params = [
            'start_date' => $startDate,
            'end_date' => $endDate
        ];

        if ($symbols) {
            $params['symbols'] = implode(',', $symbols);
        }

        return $this->makeRequest('/timeseries?' . http_build_query($params));
    }

    public function getStatus(): array
    {
        $ch = curl_init();
        curl_setopt_array($ch, [
            CURLOPT_URL => $this->baseURL . '/status',
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_TIMEOUT => 10
        ]);

        $response = curl_exec($ch);
        curl_close($ch);

        return json_decode($response, true);
    }
}

// Usage
$api = new ExchangeRatesAPI($_ENV['EXCHANGE_RATES_API_KEY']);

try {
    $rates = $api->getLatestRates();
    echo "USD Rate: " . $rates['rates']['USD'] . "\n";
    
    $conversion = $api->convert('AUD', 'USD', 100);
    echo "100 AUD = " . $conversion['result'] . " USD\n";
} catch (Exception $e) {
    echo "Error: " . $e->getMessage() . "\n";
}

Using Guzzle HTTP

<?php

require_once 'vendor/autoload.php';

use GuzzleHttp\Client;
use GuzzleHttp\Exception\RequestException;

class ExchangeRatesAPIClient
{
    private $client;
    private $apiKey;
    private $baseURL = 'https://api.exchangeratesapi.com.au';

    public function __construct(string $apiKey)
    {
        $this->apiKey = $apiKey;
        $this->client = new Client([
            'base_uri' => $this->baseURL,
            'timeout' => 30,
            'headers' => [
                'Authorization' => 'Bearer ' . $this->apiKey,
                'Content-Type' => 'application/json',
                'User-Agent' => 'PHP-Guzzle-ExchangeRatesAPI/1.0'
            ]
        ]);
    }

    private function makeRequest(string $endpoint): array
    {
        try {
            $response = $this->client->get($endpoint);
            $data = json_decode($response->getBody()->getContents(), true);
            
            if (!$data['success']) {
                throw new Exception('API Error: ' . $data['error']['info']);
            }
            
            return $data;
        } catch (RequestException $e) {
            if ($e->hasResponse()) {
                $response = json_decode($e->getResponse()->getBody()->getContents(), true);
                throw new Exception('API Error: ' . ($response['error']['info'] ?? $e->getMessage()));
            }
            throw new Exception('Network Error: ' . $e->getMessage());
        }
    }

    public function getLatestRates(): array
    {
        return $this->makeRequest('/latest');
    }

    public function convert(string $from, string $to, float $amount, ?string $date = null): array
    {
        $query = http_build_query(array_filter([
            'from' => $from,
            'to' => $to,
            'amount' => $amount,
            'date' => $date
        ]));

        return $this->makeRequest('/convert?' . $query);
    }

    public function getTimeSeries(string $startDate, string $endDate, ?array $symbols = null): array
    {
        $query = http_build_query(array_filter([
            'start_date' => $startDate,
            'end_date' => $endDate,
            'symbols' => $symbols ? implode(',', $symbols) : null
        ]));

        return $this->makeRequest('/timeseries?' . $query);
    }
}

// Usage
$api = new ExchangeRatesAPIClient($_ENV['EXCHANGE_RATES_API_KEY']);

try {
    $rates = $api->getLatestRates();
    print_r($rates);
} catch (Exception $e) {
    echo "Error: " . $e->getMessage() . "\n";
}

Laravel Integration

Service Provider

<?php
// app/Providers/ExchangeRatesServiceProvider.php

namespace App\Providers;

use Illuminate\Support\ServiceProvider;
use App\Services\ExchangeRatesService;

class ExchangeRatesServiceProvider extends ServiceProvider
{
    public function register()
    {
        $this->app->singleton(ExchangeRatesService::class, function ($app) {
            return new ExchangeRatesService(config('services.exchange_rates.api_key'));
        });
    }

    public function boot()
    {
        //
    }
}

Configuration

<?php
// config/services.php

return [
    // ... other services

    'exchange_rates' => [
        'api_key' => env('EXCHANGE_RATES_API_KEY'),
        'base_url' => env('EXCHANGE_RATES_BASE_URL', 'https://api.exchangeratesapi.com.au'),
        'timeout' => env('EXCHANGE_RATES_TIMEOUT', 30),
    ],
];

Service Class

<?php
// app/Services/ExchangeRatesService.php

namespace App\Services;

use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Cache;
use Illuminate\Support\Facades\Log;

class ExchangeRatesService
{
    private $apiKey;
    private $baseURL;
    private $timeout;

    public function __construct(string $apiKey)
    {
        $this->apiKey = $apiKey;
        $this->baseURL = config('services.exchange_rates.base_url');
        $this->timeout = config('services.exchange_rates.timeout');
    }

    public function getLatestRates(bool $useCache = true): array
    {
        $cacheKey = 'exchange_rates_latest';
        
        if ($useCache && Cache::has($cacheKey)) {
            return Cache::get($cacheKey);
        }

        try {
            $response = Http::timeout($this->timeout)
                ->withHeaders(['Authorization' => 'Bearer ' . $this->apiKey])
                ->get($this->baseURL . '/latest');

            $data = $response->json();

            if (!$data['success']) {
                throw new \Exception('API Error: ' . $data['error']['info']);
            }

            // Cache for 30 minutes (RBA updates daily at 4 PM AEST)
            Cache::put($cacheKey, $data, now()->addMinutes(30));

            return $data;
        } catch (\Exception $e) {
            Log::error('Exchange Rates API Error: ' . $e->getMessage());
            
            // Return cached data if available
            if (Cache::has($cacheKey)) {
                Log::info('Returning cached exchange rates due to API failure');
                return Cache::get($cacheKey);
            }
            
            throw $e;
        }
    }

    public function convert(string $from, string $to, float $amount, ?string $date = null): array
    {
        $params = [
            'from' => $from,
            'to' => $to,
            'amount' => $amount
        ];

        if ($date) {
            $params['date'] = $date;
        }

        $response = Http::timeout($this->timeout)
            ->withHeaders(['Authorization' => 'Bearer ' . $this->apiKey])
            ->get($this->baseURL . '/convert', $params);

        $data = $response->json();

        if (!$data['success']) {
            throw new \Exception('API Error: ' . $data['error']['info']);
        }

        return $data;
    }

    public function getRate(string $currency, bool $useCache = true): ?float
    {
        try {
            $rates = $this->getLatestRates($useCache);
            return $rates['rates'][$currency] ?? null;
        } catch (\Exception $e) {
            Log::error('Failed to get rate for ' . $currency . ': ' . $e->getMessage());
            return null;
        }
    }

    public function convertAmount(float $amount, string $from, string $to): ?float
    {
        try {
            $conversion = $this->convert($from, $to, $amount);
            return $conversion['result'];
        } catch (\Exception $e) {
            Log::error('Failed to convert ' . $amount . ' ' . $from . ' to ' . $to . ': ' . $e->getMessage());
            return null;
        }
    }
}

Controller Usage

<?php
// app/Http/Controllers/ExchangeRateController.php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Services\ExchangeRatesService;

class ExchangeRateController extends Controller
{
    private $exchangeRatesService;

    public function __construct(ExchangeRatesService $exchangeRatesService)
    {
        $this->exchangeRatesService = $exchangeRatesService;
    }

    public function index()
    {
        try {
            $rates = $this->exchangeRatesService->getLatestRates();
            
            return response()->json([
                'success' => true,
                'data' => $rates
            ]);
        } catch (\Exception $e) {
            return response()->json([
                'success' => false,
                'error' => $e->getMessage()
            ], 500);
        }
    }

    public function convert(Request $request)
    {
        $request->validate([
            'from' => 'required|string|size:3',
            'to' => 'required|string|size:3',
            'amount' => 'required|numeric|min:0'
        ]);

        try {
            $result = $this->exchangeRatesService->convert(
                $request->input('from'),
                $request->input('to'),
                $request->input('amount')
            );

            return response()->json([
                'success' => true,
                'data' => $result
            ]);
        } catch (\Exception $e) {
            return response()->json([
                'success' => false,
                'error' => $e->getMessage()
            ], 500);
        }
    }
}

Error Handling & Logging

<?php

class ExchangeRatesAPIWithRetry
{
    private $apiKey;
    private $baseURL;
    private $maxRetries;
    private $retryDelay;

    public function __construct(string $apiKey, int $maxRetries = 3, int $retryDelay = 1)
    {
        $this->apiKey = $apiKey;
        $this->baseURL = 'https://api.exchangeratesapi.com.au';
        $this->maxRetries = $maxRetries;
        $this->retryDelay = $retryDelay;
    }

    private function makeRequestWithRetry(string $endpoint, int $attempt = 1): array
    {
        try {
            $ch = curl_init();
            curl_setopt_array($ch, [
                CURLOPT_URL => $this->baseURL . $endpoint,
                CURLOPT_RETURNTRANSFER => true,
                CURLOPT_HTTPHEADER => [
                    'Authorization: Bearer ' . $this->apiKey,
                    'Content-Type: application/json'
                ],
                CURLOPT_TIMEOUT => 30,
                CURLOPT_CONNECTTIMEOUT => 10
            ]);

            $response = curl_exec($ch);
            $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
            $error = curl_error($ch);
            curl_close($ch);

            if ($error) {
                throw new Exception('cURL Error: ' . $error);
            }

            $data = json_decode($response, true);

            if ($httpCode >= 400 || !$data['success']) {
                $errorInfo = $data['error']['info'] ?? 'Unknown error';
                $errorCode = $data['error']['code'] ?? $httpCode;
                
                // Don't retry client errors (4xx)
                if ($httpCode >= 400 && $httpCode < 500) {
                    throw new Exception("API Error $errorCode: $errorInfo");
                }
                
                throw new Exception("Server Error $errorCode: $errorInfo");
            }

            return $data;
        } catch (Exception $e) {
            error_log("Attempt $attempt failed: " . $e->getMessage());

            // Don't retry authentication or client errors
            if (strpos($e->getMessage(), 'API Error 4') === 0) {
                throw $e;
            }

            // Retry on network errors and server errors
            if ($attempt < $this->maxRetries) {
                sleep($this->retryDelay * $attempt);
                return $this->makeRequestWithRetry($endpoint, $attempt + 1);
            }

            throw $e;
        }
    }

    public function getLatestRatesSafe(): array
    {
        try {
            return $this->makeRequestWithRetry('/latest');
        } catch (Exception $e) {
            error_log('Failed to fetch latest rates after retries: ' . $e->getMessage());
            
            // Try to return cached data
            $cached = $this->getCachedRates();
            if ($cached) {
                error_log('Using cached rates due to API failure');
                return array_merge($cached, ['fromCache' => true]);
            }
            
            throw new Exception('Unable to fetch exchange rates. Please try again later.');
        }
    }

    private function getCachedRates(): ?array
    {
        $cacheFile = sys_get_temp_dir() . '/exchange_rates_cache.json';
        
        if (file_exists($cacheFile)) {
            $cached = json_decode(file_get_contents($cacheFile), true);
            
            // Check if cache is less than 1 hour old
            if (time() - $cached['cachedAt'] < 3600) {
                return $cached['rates'];
            }
        }
        
        return null;
    }

    private function setCachedRates(array $rates): void
    {
        $cacheFile = sys_get_temp_dir() . '/exchange_rates_cache.json';
        $cacheData = [
            'rates' => $rates,
            'cachedAt' => time()
        ];
        
        file_put_contents($cacheFile, json_encode($cacheData));
    }
}

Next Steps

Python SDK

Python examples and best practices

cURL Examples

Command-line examples and shell scripts

JavaScript SDK

JavaScript/Node.js examples and React hooks

API Reference

Complete API documentation

Client Libraries

​Installation

​Quick Start

​Basic PHP Class

​Using Guzzle HTTP

​Laravel Integration

​Service Provider

​Configuration

​Service Class

​Controller Usage

​Error Handling & Logging

​Next Steps

Python SDK

cURL Examples

JavaScript SDK

API Reference

Installation

Quick Start

Basic PHP Class

Using Guzzle HTTP

Laravel Integration

Service Provider

Configuration

Service Class

Controller Usage

Error Handling & Logging

Next Steps